this is going off-topic, so i hope to make this a last post on PICs.
the frequency counting code for PICs is pretty nifty and it does the timing based on execution times of its own code and reads off the number of cycles-ticks tha accumulate in the timer register.
you can go through david tait's excellent archives on the net to get you started. i have used microchip's own IDE to simulate, debug and assemble the pic programs (written in assembly ofcourse).
the frequency counters based on PIC invariably use the code given in an application note that you can download from their website on www.microchip.com.
- farhan
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On Mon, 11 Jul 2005, Sam Caldwell wrote:
the PIC timer can be used to accurately measure the oscillator frequency
(as normal PIC based frequency counters do) instead of displaying the
frequency on a display, it can (in addition) also pump a capacitor that
in turn is used to bias a varactor across the VFO.
As a latecomer to pics and picaxes I have managed to stumble through
some of the basics, but causing a number of LEDs to come on and off is
hardly exciting.
I have assembled a kitset frequency counter without having a clue as
to how it worked, because the chip was preprogrammed.
Can anyone point me towards an internet source where I might get an
explanation of how a pic ( or picaxe ) might be used for this purpose,
i.e what the program has to do, and why.
Regards, Sam C. ZL1SAM
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